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PERCEPTIONS
Gallery I
Naturally Finished Wood Models Contact DOXAERIE |
STRATOLINER MODEL RESTORATION
Some time ago I was sent photos and asked to identify a
very large, dark, four engined model. It was a Boeing 307 Stratoliner, but the
question was also whether it represented a wind tunnel model. Its owner, Shortly after that, I was given a copy of an article
written by O. Phillip Dickert, "Big Ones, Little Ones," published in the April,
1939, issue of Popular Aviation. Dickert, a Boeing model maker, built wind
tunnel models for the Stratoliner and described in detail their sizes and
construction. The owner was given the model some years ago by a person who said he found it
in an antique store. Further photos sent me verified that the model was quite
old and that some markings, specifically windows, had been overpainted by a coat
of dark gray paint applied to the whole model.
The model was nowhere near me physically, so my early
efforts at identifying the model were done by simply viewing photos and
researching on the internet. I was helped by a number of persons, Dave Ostrowski
(who, at viewing a pre-restoration photo, dubbed it the "Gray Beast"), Steve
Remington, Anthony Lawler, John Aldaz, and Francois Renaud who sent me a scan of
the large Stratoliner Various sources indicate that TWA spent a good deal of
money on its 1940 ad campaign to promote the first transcontinental flights of
the Stratoliner. One source opined that TWA had finally pulled itself out of the
red by 1939 only to go back into the red because of this expensive ad campaign. If I could verify that the Gray Beast was of the same series as the other models, then I could confirm its origins and historical value as well as have an idea how to restore it. There were two ways to do this: First, by using Dave’s photos and the minute description of the model he provided to analyze the photos I had, and, second, by actually taking the model apart, removing paint layer by layer to discover what lay under that horrible dark gray final coat of paint. In actuality, I had to pursue the first course of action as far as possible in order to convince the owner that it was worth it to have me take possession of the model to do the second. Both proved fruitful. The NASM model, while colorful and impressive, is
immediately interesting for what it does not include. There is very
little
Based on the NASM photos, I asked the son-in-law of the owner to lightly sand the vertical tail to see if there was any evidence of the two red TWA stripes prominently displayed on the NASM model. He was reluctant to get too deeply into the paint, but very soon discovered red in the rudder seam in just the right place. At that point I thought there was little doubt that Gray Beast was a sister ship to the NASM model. The owner agreed, and I was able to pick up the model at his home. I was reluctant to admit to him that I subsequently broke off a wing while trying to get it back to my shop, some two thousand miles distant! This turned out fortuitously as examination showed the wing root had been badly cracked previously and this and the vertical tail had been broken off before. In the event, I completely disassembled the model anyway during restoration. PAINT REMOVAL My first step was to remove paint layer by layer. This proved very interesting and as usual in these restorations, more questions were raised than for which I have found answers. I started with the tail. Apparent was the fact that its outline was not exactly right. Maybe it once was, but the trailing edge had been badly chipped away. This was true for horizontal tail surfaces as well as trailing edges of wings. As the paint started coming off, I quickly discovered that not all areas had the same sequence of fillers and paints, but it roughly worked out to the following from the original wood up: Tan "plastic wood" type filler at the base of the fin and this was added to in some areas with a reddish brown filler. In other areas a thin, bluish green filler was found. Interestingly, and very puzzling to me, was the fact that filler completely filled in the rudder outline that was cut into the surface obliterating about two thirds of this outline on one side, and about one third on the other. This was done before any primer or paint was applied. Why? I don’t know. Dave had reported that his close-up examination of the NASM model showed that it had been fairly roughly finished. Yet there is no excuse for a professional model being this sloppily finished and I began to wonder if this was, indeed, one of the ad campaign models. The next coat up was a very thick white paint that was
obviously a primer and found in various thickness over all the model. Over this,
in places, was more of the red filler, then the silver which I surmised was the
original finish coat for this model, as all red markings subsequently found were
on this lowest coat of silver paint.
Next I went to the wing tops and took off layers. I was
looking for the black registration numbers on the bottom silver coat. On the
right wing I went down through the layers too fast and found nothing. But the
bottom up paint sequence was somewhat different than found on the tail. Lowest
was the white undercoat (with fillers around wing root and engines), the
original silver, but now a heavy black overcoat before another silver, then
black around the nacelles extending back towards the trailing edge, then a dark
gray, a green and then on top, the final dark gray that covered the entire
model.
Later, on the fuselage, I discovered the remnants of the
red TWA in a circle under the cockpit on both sides, but no trace of the letters
of "The Intercontinental Line" above the windows. The windows were interesting,
as well. Each corner was identified by a pin hole, all attached by scribed
lines. The "eyebrow" windows on the right side of the fuselage were not found. The thickest and the greatest number of paint layers, some 10 of them, were found in the nacelle fronts where an entirely new color was found next to the wood, a very bright blue-green under various other colors in an order not found on the rest of the model. A final note on the old paint coats and fillers. Just that. They all looked very old, cracked and checked, as if the model had been originally completed, then almost immediately more fillers and more paints were added at just about the same time. That all of this was done in the original model shop is made more likely by the fact that all coats appeared to have been applied by a spray gun. Brush strokes were found only on the markings. Perhaps with the exception of the final dark gray coat (and even that was old), nothing but natural deterioration happened to the model over the last 60 or 65 years. THE REBUILD After having satisfied myself that I had recorded all the layers of paint (what is presented here is but a summary of my underway notes) and learned what I could from them, I removed the rest of the paint down to the original pine from which the model was constructed. I had become a bit disappointed at the sloppiness with which the model had been finished and was still questioning myself if this was a truly professional job. But now I had a chance to see the model before the finish went on. Would it give me a better opinion of it? With all the paint off, the model was still together with
the exception of the left wing. I had noticed before that the wing root posed a
perplexing issue: It looked as though the airfoil was upside down.
Is this good restoration practice? Bob Mikesh, who wrote Restoring Museum Aircraft, might say no. But I started rationalizing. I had already decided to correct the vertical tail outline to more closely match that of the NASM model, and I began to think that this model might have been a shop prototype for the whole series given all the different paints and fillers applied apparently one after the other early in the model’s existence. The forward fuselage shape was also a bit fat in comparison to the NASM model and true scale outline of the Stratoliner. Other flaws included off center prop shaft holes and the stand mounting hole drilled a full 3 inches forward of the center of gravity. It wouldn’t balance on my working stand unless the latter was clamped to the workbench. The root chord of each wing differed, and the tail end of the fuselage turning was left blunt. I concluded then and remain convinced that this model was a test shot and probably never issued to TWA. It may have been given to a worker or his child and gone into the family attic for many years. Restoring it to its flawed and incomplete state didn’t seem worth the effort, so restoring it to what its maker had intended for it, using the NASM model as a guide, seemed reasonable. But was I really sure it was, finally, a professional model and a sister ship to the NASM model? My previous evaluations of the likenesses were solidified as I disassembled the model. It had actually been very carefully thought out and designed. The joints of any very large solid model made from only a couple of pieces of wood are going to work and eventually crack and spit out fillers and paint on the seams. Many of the large display models of this period have this problem. I once saw a roomful of the 1946 Bell model shop efforts done in solid wood and beautifully lacquered. Many, if not most of the joints had broken out. A pity. But the Stratoliner model maker, or at least the one who designed it (and I now tend to think of them as two different people), did what had to be done to attempt to prevent this. He designed it with laminated wood, grains running in opposite directions, so small pieces wouldn’t have the strength to move much, and if they did, would work against each other. Thus the larger laminate wouldn’t work that much, if at all, against other laminates. Taking off the tails, I discovered they were laminated up
of three edge glued pieces of pine. The wing had four laminations. Engine nacelles were laminated up of three lifts, as well. This was pre-war America. The designer didn’t have to do this. There was plenty of large stock around. But he designed it properly to last. The machining and gluing of the laminates was neatly and precisely done. I found that tail surfaces were doweled, glued and nailed into place. Wings were doweled and glued, nacelles nailed and glued. When reassembling the model, I replaced all dowels, deleted the nails and used epoxy glue. When the model was completely
In the case of the misshapen vertical fin, I separated the
rudder Reversing the wings was a bit of a chore. I would not have
removed the nacelles except for this. The wing root angle for the dihedral was,
of course, now all wrong and when I corrected it, the wing was too short. Since
according to the Matt plans, the outboard chord was a bit narrow and the tips
had been badly bashed about,
I also reduced slightly the diameter of the fuselage
forward of the wings to better match up to scale and the NASM model. The
mounting hole was moved back to the center of gravity and lined with brass
tubing. The model now being fully reassembled, PC Woody, a
wood epoxy paste (also makers of PC 7 and PC 11 epoxy pastes), was used
Dave’s photos of the NASM model also proved helpful for
designing and carving the rather Art Nouveau inspired stand for the model. I had acquired a Maquette 1/72nd plastic and
resin kit of the Stratoliner simply for the decal sheet. I had hoped to enlarge
parts of it as a basis for the decal sheet I had intended to do for the TWA
model. But it was, for the most part, inaccurate and I used mainly the Matt
drawings as a basis for my markings. The original model had markings and
lettering hand painted. Careful examination of the NASM model showed it was
pretty roughly done, but still a lot better than my hand lettering skills would
have accomplished. A funny note on the NASM model hand lettering: A long time on the computer resulted in a passable
sheet of graphics for the model, and I used a laser copier to print them on a
clear decal sheet. Better than new? Yes, probably, given what "new" may have
actually looked like. Not really a "pure" restoration in that sense, but I think
justified. In any event, the model is a genuine survivor from the Golden Age and
represents the promotion of a significant event in American aviation history:
the first transcontinental flights by a four engined, pressurized airliner. It
gains more relevance with the recent restoration and presentation to the
National Air and Space Museum of the last surviving Stratoliner. However, I
remain somewhat perplexed by the typical reaction of people to the model: "Oh,
what a beautiful stand." Doug Emmons 2005 Addendum: Prior to reassembling all parts, I inserted a "time capsule"
into the hollow fuselage that consisted of what I knew of the history of the
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